Hair clipper



HAIR' CLIPPER Filed Aug. 26. 1936 2 Sheets-Sheet l I IN" W 29 25' d 15 25 4 i j y l VENTOR) Oct. 5, 1937. E. HAMMERLING 2,094,651

HAIR \CLIPPER Filed Aug. 26. 1956 2 Sheets-Sheet 2 75.5 INVENTOR,

Patented Oct. -5, 1937 UNITED STATES PXTENT OFFICE 9 Claims.

This invention relates to hair clippers, and more particularly to close cutting clippers useful as dry shaving razors.

A general object of the invention is to provide improved clippers or dry shaving razors which are capable of giving a very close, comfortable and eflicient shave.

More particularly, objects of the invention are to provide improved clippers or razors which quickly and efllciently shear hair at a point very close to the skin, and which are adapted to remove substantially all of the hair in their path at each stroke, thus reducing largely the need for repeated stroking over the same area.

Other objects are to provide clippers or razors having an improved skin contacting surface adapted to present the skin and hair closely adjacent a shearing blade, which are safe, have their working parts assembled with precision, are simple and rugged in construction, and have a very long service life.

Further objects are to provide clipper or razor parts having improved features of construction leading to improved results *in the assembled razor.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the features of construction, combination of elements and arrangement of parts, which will be exemplified in the construction hereinafter set forth and the scope of the invention will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:

Fig. l is a front elevation of an assembled razor embodying features of the invention;

Fig. 2 is a top plan view, on enlarged scale, of a cutting head embodying features of the present invention;

Fig. 3 is a longitudinal vertical sectional view taken along line 3-3 of Fig. 2;

Fig. 4 is a transverse vertical sectional view taken along line 4-4 of Fig. 3;

Fig. 5 is a transverse vertical sectional view taken along line 5-5 of Fig. 3, and showing the interior cutter in a different position from that illustrated in Fig. 4;

Fig. 6 is a top plan view of the interior cutter shown in Figs. 2 to 5;

Fig. 7 is a bottom plan view of such cutter;

Fig. 8 is a transverse sectional view, on a further enlarged scale, showing details of the constrtuction of the housing accommodating such on .er;

Figs. 9, 10 and 11 are perspective views showing other forms of cutters;

Fig. 12 is a top plan view of a cutter head similar to that of Fig. 2 but having another form of interior cutter, part thereof being broken away better to show the cutter construction;

Fig. 13 is a transverse sectional view taken along line Iii-I3 of Fig. 12;

Fig. 14 is a top plan view of another form of cutter head embodying principles of the invention;

Fig. 15 is a transverse sectional view taken along line |5.-|5 of Fig. 14;

Fig. 16 is a top plan view of another form of interior cutter useful with the housing shown in Fig. 14;

Fig. 17 is a fragmentary transverse sectional 20 view on an enlarged. scale showing the cutter along line ll-l'l of Fig. 16 and showing its relation with the outer housing;

Fig. 18 is a top plan view of another form of cutting head, part thereof being broken away better to show the interior construction;

Fig. 19 is a transverse sectional view along line Iii-l9 of Fig. 18;

Fig. 20 is a top plan view of another form of cutter head, part thereof being broken away better to show the interior construction and Fig. 21 is a transverse sectional view along line 2l-2l of Fig. 20.

Referring more particularly to the drawings, there is shown in Fig. 1 a combined handle and 35 motor casing l0 adapted to hold a rotatable electric motor, the shaft II (Fig. 3) of which extends upwardly and terminates in an eccentric crankpin l2. The upper end of the motor casing has a channel adapted to receive the lower end of a detachable cutter head which is fastened in such channel by a set screw l3. An exposed thumb wheel I is fixed to the shaft it to enable the operator to start the motor, or to adjust the eccentric l2 when assembling the cutter head and the motor casing. The parts thus far described with the exception of the cutter head are of conventional design and form no part of the present invention except insofar as they are used in combination with novel or improved features, of the cutter head about to be described. Any other suitable or convenient type of driving mechanism may be employed to give the required movement to the cutting parts. The motor may be of the buzzer type instead of rotata- 55 ble, or a flexible drive shaft may be run from a remote rotatable motor, and other driving connections than an eccentric pin may be used between the motor and cutter head, so long as a driving movement suitable to the cutter action is provided.

In one desirable form, the cutter head comprises an outer housing l5 having an interior cy lindrical bore IS. The outer contour of the housing may also preferably be generally cylindrical with its surface eccentric to that of the bore and most closely approaching the bore surface near the top or the outer surface of the housing. However, any other suitable outward configuration of the housing may be employed, although it is desirable that its upper portion should be generally convex, except in the shearing area where this generalconvexity is preferably altered in a manner hereinafter described.

The housing is provided in its upper thin wall with a longitudinal slot, one side 11 of which preferably extends parallel with the longitudinal axis of the housing and meets the cylindrical surface of the inner bore along a shearing edge. This slot is sufficiently wide readily to accommodate a hair, but within this limiting factor should be made narrow enough to prevent the skin from entering and being pinched therein. The shearing edge I! of the slot is continuous and extends nearly from end to end of the housing, as illustrated.

The housing is also preferably provided with a plurality of teeth l8 separated by spaces leading into the longitudinal slot. These spaces are sufliciently wide to accommodate a hair of maximum thickness, the entire spaced tooth arrangement forming a comb for leading hair into the longitudinal slot and against the shearing edge II.

According to one desirable feature of this invention, the housing is then hollow-ground along the curve indicated at A in Fig. 8. This curve is nearly tangent to the cylindrical surface of the interior bore l6 precisely along the shearing edge l1, and the hollow grinding provides a concave depression in the outer face of the housing which extends from both sides of the housing slot. This grinding provides a very fine edge at II, which may conveniently vary from .0025 to .004 inch, or may be even sharper if desired. However, it is still a shearing edge as distinguished from a draw cutting or razor edge, and has a shearing corner where it meets the bore IS. The grinding along curve A extends upwardly rather abruptly from the edge I! and meets the convex outer surface of the housing along a ridge IS. The teeth l8 at the other side of the slot are also thinned by the grinding along curve A, but not necessarily so much as shearing edge I1. These teeth may be further ground at 20 to merge theirouter end surfaces smoothly into the general cylindrical or convex contour of the housing. Both the housing adjacent the shearing edge I! and the teeth are ground so as to retain suflicient thickness and strength to provide a rigid, self-sustaining structure. When the housing is moved in the direction of the arrow in Fig. 8 against the skin, the ridge l9 causes the skin to bulge outwardly into the concave depression formed by the hollow grinding so that the peak of a convex bulge of skin is pressed closely against the fine shearing edge II, the hair extending from the peak of such skin bulge being led between the teeth l8 up against the shearing edge where it is adapted to be cut off at the surface of the interior bore I6 by means of a cutter such as those about to be described.

In the form shown in Figs. 2 to '7, a cutter 2| is snugly fitted in the bore l6. It is generally cylindrical in form and has cylindrical surfaces closely fitted in and guided by the bore, these guided cylindrical surfaces preferably comprising at least a major portion of the outer cutter surfaces. The cutter is preferably hollowed or otherwise designed to receive cut hair, and is openended at at least one end so that the hair dropping into it may fall out. In the presently described form, the hair receiving interior of the cutter comprises a hollow cylindrical bore 22 which may be eccentric to the cutter axis to provide more material on the under-side of the cutter to accommodate the hereinafter described driving and guiding mechanism. The upper portion of the cutter is provided with a longitudinal groove or slot 23, which, when the cutter interior is hollowed, communicates with such hollow. The side 24 of this groove or slot which faces the shearing edge l1 meets the outer cylindrical surfaces of the cutter along a shearing edge and this side is preferably, though not necessarily, under-cut to provide an acute shearing edge. This shearing edge at 24 is also preferably positioned at a slight bias to the longitudinal axes of the cutter and housing so that it has a bias with respect to the shearing edge I! and is adapted to shear progressively along such edge as it is wiped across its under-side. This biased relation of the shearing edges is best illustrated in Fig. 2, which shows the cutter and housing in their relative positions just at the beginning of a shearing stroke.

The under-side of cutter 2| is provided with a longitudinal recess 25 of a width closely to accommodate the eccentric driving pin l2, and preferably of a length to permit such pin to ride therealong between the longitudinal limits of its eccentric throw. Near its ends, the under-side of the cutter 2| is provided with transverse recesses 26 and 21 adapted to accommodate spring pressed detents 28 and 29 which extend slightly beyond the bottom of the bore IS. The springs for such detents may conveniently be accommodated in seats provided in a base 30 of the cutter head which is adapted to fit in the channel across the top of motor casing l and which is attached to the housing l by means of screws 3|.

The interior cutter 2| may he slipped endwise into the bore l6 where it is held in position by the detents. The cutter head, thus assembled, may be fitted down into the channel in the motor casing until the pin l2 enters the recess 25, the thumb wheel I4 providing for suitable manipulation to register these parts whereupon the cutter head may be clamped in place by the set screw l3. The recess 25 and the shearing edge at 24 are relatively positioned so that the pin l2 upon rotation of the shaft II is adapted to wipe the edge 24 just beyond the edge H at one limit of its eccentric throw and is adapted to bring the slot 23 beneath the longitudinal housing slot to the position illustrated in Fig. 4 at the other end of its eccentric throw. The cutter is substantially limited to back and forth oscillatory movement by the grooves 26 and 21 and detents 28 and 29. However, if desired, the interior cutter may be given a combined oscillatory and longitudinal movement by eliminating the detents and forming recess 25 snugly to surround pin l2 so that the cutter may partake of the full movement of such pin instead of having a harmonic oscillatory movement only.

In operation, the above described form of clipper or razor is drawn along the surface of the skin in the direction of the arrow shown in Fig. 8. Hair enters the spaces between the teeth I8 and is led into the housing slot and into the underlying cutter groove 23 when the cutter is in the position shown in Fig. 4. This hair is then sheared close to the skin surface between the edges i1 and 24 as the cutter oscillates along its shearing; stroke. The shearing edge I! being continuous and substantially perpendicular to the direction '-'of the razor stroke, clips substantially all of the hair in its path, this hair being free to enter unrestrictedly into the housing slot after its release-by the comb structure at l8.

The cutter shown in Fig. 9 is also adapted to be used with the above described head l5. This cutter comprises a cylindrical barrel I 2| which is hollowed at I22 by extending the groove or slot I23 well into the interior of the cutter body. One edge I24 of this groove or slot is preferably undercut to meet the cylindrical outer surface of the cutter along an acute shearing edge. This cutter is adapted to be driven by a pin l2 in the same manner as cutter 2|.

In Fig. 10 the cutter 22| is provided with a longitudinal groove or slot 223 having a V-section, one side 224 of which meets the cylindrical cutter surface along a preferably acute shearing edge. Hair dropping into this groove or slot is adapted to be passed out the open ends of the cutter.

The cutter shown in Fig. 11 is formed of rolled 7 sheet metal which may desirably-have a slight spring outwardly against the walls of housing bore (6. This cutter, designated 32!, has its terminal edges spaced to providea groove or slot 323 communicating with its hollow interior 322. One side 324 of this groove or slot forms a shearing edge adapted to cooperate with the shearing edge ll of the housing. The under-side of this cutter is provided with suitable driving and guiding recesses or openings, as is the cutter shown in Fig.

Another form of cutter is shown in the assembly illustrated in Figs. 12 and 13. Here an outer housing l5 having a shearing edge I! is provided in accordance with the construction illustrated in Fig. 2, except that here the longitudinal housing slot may be made somewhat wider, if desired. A cutter 42l is provided having a cylindrical contour adapted to fit snugly in the bore l6 of the housing and having a hollow interior 422. A longitudinal slot is provided in the cutter having an undercut side 424 which meets the cylindrical surface of the cutter along a shearing edge. The opposite side of this slot is bounded by a plurality of cutter teeth 32, the ends of which approach closely, but preferably do not meet, the shearing edge at 424. The space between this shearing edge and the ends of the teeth 32 is less than that of the width of the housing slot adjacent shearing edge I 1, so that the teeth 32 provide a support preventing the skin from entering this slot and being pinched'against the edge II. The teeth 32 register with and are preferably somewhat narrower than the bollsing teeth l8, and the cutter is oscillated in the same way as the above described forms so that this registry is maintained during operation.

In Figs. 14 and 15 a cutter head having a double cutting stroke is shown. Here an outer housing H5 is provided which may be of generally cying slot so that it will not be iindrical or convex outer contour and which has a cylindrical interior bore H6. The upper side of this housing is provided with a longitudinal groove low interior 522. The uppersurface of this cutter is provided with a series of longitudinal shearing edges 524 and 524' separated by skin supporting ribs 33. This cutter is adapted to be oscillated, or oscillated and reciprocated, in the same manner as the cutter in the first described form, whereupon its shearing edges 524 and 524 respectively wipe across the shearing edges 5|! and 5".

Fig. 16 shows a cutter adapted to be used with the head 5l5 which is similar to the cutter described in connection with Fig. 14 except that its skin separating ribs 33 are cut away at 34 to provide continuous shearing edges 524 and 524'. The operation is otherwise the same as that described in connection with Fig. 14, and in each of these last two described forms the ribs 33 provide a support adapted to keep the skin out of the houspinched against the edges 5|! and 5H,

The assembly shown in Figs. 18 and 19 is also adapted to give a double shearing action along longitudinal shearing edges. Here a housing 6l5 which may be of general cylindrical form is provided with two longitudinal slots respectively forming shearing edges 6 and 6H. A plurality of comb teeth 6! and Bill respectively approach these shearing edges. In the illustrated form, both sides of the housing are hollow-ground so that a fine shearing edge is provided at GI! and 6" as is shown in Fig. 19. The strap formed by the housing material between these shearing edges is integral with the housing but is prefere ably ground down along its top surface at 35 to permit the skin to approach the shearing edges more closely. In order to support and rigidity this strap a bar or beam 36 is riveted therebeneath, the unground end portions 31 of the housing providing a strong mounting for such bar. The cutter 52| is generally cylindrical and is fitted snugly within the cylindrical housing bore GIG. It is hollowed at 622 and has a wide groove or slot in its upper side having sides 524 and 524' respectively adapted to cooperate with the blades El! and 6H in shearing relation, when the cutter is oscillated by means such as those described above.

In Figs. 20 and 21 a cutter head assembly is shown which has a double shearing action somewhat similar to that of the head shown in Fig. 14. Here an outer housing H5 is provided having a cylindrical interior bore H6. .A pair of longitudinal slots are provided which respectively meet this bore along shearing edges H1 and H1. The outer surfaces of the housing are hollowground to form a pair of concave depressions extending from each side of theserespective slots, leaving a central strap which is also preferably ground somewhat at 135. A cutter 'I2l is provided which is generally cylindrical in form and fits snugly in the housing bore 1| 6. This cutter is recessed on opposite sides to provide shearing edges I24 and 124' respectively adapted to cooperate with the shearing edge at H1 and H1. The cutter "I is adapted to be driven in the same manner as the cutters in the above described forms so as to wipe its shearing edges across the housing shearing edges. Hair clipped at these edges is adapted to drop into one or the other of the cutter recesses whence it may pass out their ends, which are left open.

In each of the above described forms of the invention each cutter bladeis preferably positioned at a slight bias with respect to its cooperating housing blade to provide a progressive shearing action. The cutter head parts are made of machine steel, and the cutter is preferably made somewhat softer than the outer housing, so that any wear occuring as the parts adjust themselves to each other will be on the cutter rather than the housing. Both parts are designed for long service life, and their mutual arrangement is such that there is little likelihood that they will get out of order.

In the forms in which only one shearing blade is provided on the housing, it is contemplated that a rotary motion may be given the cutter if desired, in lieu of an oscillatory motion. If such rotary motion is provided, the cutter may have a plurality of longitudinal grooves or slots extending inwardly from its cylindrical surfaces and communicating with its hollow interior to dispose of the sheared hair.

Since certain changes may be made in the above article, and different embodiments of the invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover' all of the generic and specificfeatures of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

' Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A hair clipper comprising an outer housing having a cylindrical bore and a pair of adjacent slots extending longitudinally of said bore, the juxtaposed sides of said slots respectively meeting the cylindrical surface of said bore along a shearing edge, a cylindrical cutter snugly fitted in and guided by said bore and having a longitudinal groove or slot, the sides of said cutter groove being spaced further apart than the juxtaposed sides of said housing slot and being arranged to meet the cylindrical surface of said cutter along shearing edges, and means for oscillating said cutter alternately to wipe each of its shearing edges across a cooperating shearing edge on said housing.

2. A hair clipper comprising an outer housing having a cylindrical bore and a pair of adjacent 'slots extending longitudinally of said bore, the juxtaposed sides of said slots respectively meeting the cylindrical surface of said bore along a shearing edge, opposed sets of teeth on said housing respectively leading into the remaining outer sides of said slots, a cylindrical cutter snugly fitted in and guided by said bore and having a longitudinal groove or slot, the sides of said cutter groove being spaced further apart than the juxtaposed sides of said housing slot and being arranged to meet the cylindrical surface of said cutter along shearing edges, and means for oscillating said cutter alternately to wipe each of its shearing edges across a cooper ating shearing edge on said housing. 7

3. In a hair clipper, the combination of a. housing, a curved blade having a shearing edge forming a portion of said housing, curved guard teeth on said housing, the shearing edge being opposed to and spaced from the ends of the guard teeth to form a slot, the blade and the teeth defining a portion of the surface of a bore in said housing, an oscillatable cutter having a shearing edge cooperating with the shearing edge of said blade, a groove in said cutter, means for actuating said cutter and resilient means received in said groove to guide said cutter and urge it into engagement with said teeth and said blade.

4. In a hair clipper, the combination of a housing, a rotatable cutter having a shearing edge in said housing, a blade on said housing having a curved inner surface terminating in a shearing edge engaging said cutter, a guard on said housing having teeth spaced from said cutter shearing edge and a curved inner surface engaging said cutter, the outer surfaces of said guard and said blade adjacent the shearing edge of the blade being hollow ground, and means for actuating said cutter.

5. In a hair clipper, the combination of a motor driven cylindrical cutter, a housing enclosing said cutter and having a convexly curved outer surface eccentric to said cutter, a shearing edge on said housing defining one side of a slot communicating with said cutter, and a concavely curved narrow surface portion on said housing at the shearing edge.

6. In a hair clipper, the combination of a motor driven cylindrical cutter, a housing enclosing said cutter having a curved outer surface eccentric to said cutter, a shearing edge and an opposed guard on the curved portion of said housing defining opposite edges of a slot communicating with said cutter, and narrow hollow ground portions on the housing at each edge of the slot.

7. In a hair clipper, the combination of a motor driven cylindrical cutter, a housing enclosing said cutter and having a convexly curved outer surface terminating in a shearing edge defining one side of a slot communicating with said cutter and a concavely curved narrow surface portion on said housing at the shearing edge.

8. In a hair clipper, the combination of a housing, a longitudinal cylindrical bore in said housing, a blade having oppositely directed cutting edges defining adjacent edges of two parallel slots communicating with the bore, guard teeth on said housing spaced from and opposing the cutting edges, an oscillatable cutter in said bore, opposed parallel shearing edges on said cutter cooperating with the shearing edges of the blade and means for oscillating said cutter.

9. In a hair clipper, the combination of an outer housing, a cylindrical bore in said housing, a blade on said housing terminating irf a shearing edge defining one edge of a longitudinal slot communicating with said bore, guard teeth on said housing spaced from and opposing the shearing edge, a cylindrical cutter in the bore, a longitudinal shearing edge defining one side of a slot in said cutter opposing the shearing edge on the housing, guard teeth on the cutter opposing and spaced from the cutter shearing edge and means for oscillating the cutter to wipe the shearing edge of the cutter across the shearing edge on the housing.

EMANUEL HAMMERLING. 

